This invention relates to servicing of automobile engines and, in particular, to routine maintenance involving changing of the engine oil and oil filter.
As is well known, a modern automobile engine is designed for longevity and relatively low maintenance. Key factor in obtaining optimum service from an engine are periodic replacement of the engine lubricating oil and oil filter. The modern automobile also embodies a host of optional features, such as air conditioning, power steering, cruise control, and power windows and locks. Additionally, styling is tending toward smaller vehicles, with the result that the engine compartment that houses the power equipment has become very cluttered. It is often very difficult to reach, much less to replace, the factoryinstalled oil filter which generally comprises a canister that is held in place against a suitable engine oil filter mount by means of a centrally threaded aperture. While such filters are installed by hand, they require the use of a special tool for removal which is not easily manipulated in a crowded engine compartment. The prior art includes a number of patents that teach relocation of the engine oil filter to a more easily accessible position in the engine compartment.
The engine includes a sump or oil pan for retaining the engine oil. Certain engine components may be "splash-lubricated" from the sump, but most are supplied with oil under pressure from an engine oil pump that is supplied with oil from the sump. The sump is fitted with a drain fitting consisting of a removable plug for draining the engine oil. Oil removal generally involves elevating the automobile on a suitable hoist to permit access to the underside thereof or crawling under the automobile to remove the drain fitting. An average automobile owner who changes the oil and oil filter doesn't have an automobile hoist at his disposal and is forced to take the latter approach. The oil change procedure is not only very messy, it is often quite dangerous. Here again, there are many prior art references that teach systems for remotely draining the engine oil by replacing the sump drain plug with a special drain fitting. There are also systems for preventing accidental draining of the oil. Any remote oil changing device must be cautiously used to guard against inadvertent operation with the undesirable result of, at best, spilling oil on the ground and, at worst, destroying the engine. With the present invention, that possibility is substantially precluded by a very simple, low cost interlock arrangement between the remote drain valve operating cable and the engine oil filter itself. Unless the oil filter has been removed, the sump drain valve cannot be operated.